Apps Phase 1: docs, examples, app-only tool filtering (#3593)

* Apps Phase 1: docs, examples, app-only tool filtering, Rx() migration

* Clarify architecture page is Prefab-specific

* Fix component reference inaccuracies and DataTable search prop

- Charts import: clarify they must come from prefab_ui.components.charts
- DataTable: searchable→search (the actual prop name), remove nonexistent
  table-level sortable prop
- Select: remove nonexistent options prop, show SelectOption children
- Tabs: default_value→value
- Fix search=True in inventory, patterns, datatable examples

* Consistent Rx usage across all examples, fix imports

* Address review: fix chart imports, Select import, docstring --stdio claims

docs/docs.json

@@ -194,8 +194,10 @@
                   "apps/overview",
                   "apps/prefab",
                   "apps/interactive-apps",
+                  "apps/components",
                   "apps/patterns",
                   "apps/development",
+                  "apps/architecture",
                   "apps/low-level"
                 ]
               },